Evaluation of Cutting Rate for Ultrasonic Work Piece Vibration Assisted Wire-EDM under Varying Amplitude of Vibration

2020 ◽  
Vol 979 ◽  
pp. 149-156
Author(s):  
Sanjay Kumar ◽  
Sandeep Grover ◽  
Ravinder S. Walia

This paper present an investigation on cutting speed of ultrasonic vibration assisted wire electrical discharge machining (US-WEDM) for High carbon high chromium D3 Steel. An extensive research study was carried out with an aim to select the optimum cutting condition with the varying amplitude of vibration in order to get the optimum cutting speed for the proposed set-up. The process was mathematically modeled using the response parameters, i.e. cutting speed under a range of control parameters and the main influencing factors were determined for cutting speed criteria Taguchi’s experimentation methodology indicated the contribution of amplitude of vibration (P=6.16%), pulse on time (P=14.54%), pulse off time (P=73.16%) and peak current (P=5.94%). Finally, the optimum parametric setting for different cutting speed arising out of study has synthesized as amplitude of vibration at level 3 (18μm), peak current level 1 (100 units), pulse on time level 2 (118 μ sec) and pulse off time level 2 (46 μ sec) and analyses in this study.

2018 ◽  
Vol 249 ◽  
pp. 02003 ◽  
Author(s):  
Bhupinder Singh ◽  
Joy Prakash Misra

Cutting speed (CS) is a key performance measure to achieve optimal utilization of the WEDM process. However, input process parameters of WEDM and combination of wire and workpiece material greatly hamper CS and hence productivity and machining efficiency. Therefore, it is essential to pick the right combination of parameters and wire and workpiece material to obtain better CS. In this paper, four process parameters: Pulse-on time, Pulse-off time, Spark-gap voltage, and Peak current were chosen to develop an empirical model for CS during WEDM of Hastelloy C22 to provide a guideline to the potential users of the technique. This paper describes the response surface methodology (RSM) based mathematical modeling for average cutting speed. Furthermore, analysis of variance (ANOVA) was applied to find out significant process parameters and it was depicted that pulse on time and peak current were the major parameters affecting CS.


The present research work is to examine & advance the latent procedure factors affecting the MRR, SR and Electrode Attire despite the fact machining of Nickel composites utilizing WEDM progression. This exertion includes investigation of the connection amid the different information route considerations like Pulse-on time(Ton), Pulse off time(Toff), Pulse Peak Current(IP), Wire substantial, Work piece material & procedure factors. In light of the picked information parameters and execution estimates L-16 symmetrical exhibit is chosen to streamline the most appropriate qualities for machining for nickel amalgams by WEDM…


Author(s):  
Suvranshu Pattanayak ◽  
Ananda Kumar Sahoo ◽  
Susanta Kumar Sahoo

Recent developments in manufacturing require holes on composite materials, especially on the carbon fiber reinforced polymer (CFRP) with smooth hole periphery, low delamination, burr formation, taper, better circularity, and a high processing speed. Its non-conductive surface (epoxy layering) limits its machining through electrical discharge machining (EDM). To overcome this limitation, an aluminum fixture has been designed to guide the copper electrode of EDM for producing holes on a CFRP sheet of 1 mm thickness at low machining complexity, cost, time, delamination, burr in hole periphery and without affecting the material’s surface quality and performance. Even components with high geometrical complexity can also be drilled through this approach. Here, a multi-quality analysis called grey relational analysis is developed for examining the hole quality attributes, considering peak current, pulse on and off time, and flushing pressure as input parameters. This approach points out the optimum factor level setting and critical parameters (pulse-on time and peak current) that regulate the hole attributes (entrance and exit diameter, circularity, taper, material removal, and tool wear rate). An artificial neural network model has been designed and trained through experimental data sets. This model can also be adopted during the determination of hole quality attributes when the parameter settings are beyond a defined boundary, as the regression analysis value is very close to 1, and model performance is 4.99e-10. Peak current = 4 A, pulse-on time = 25 µs, pulse-off time=25 µs, and flushing pressure = 0.6 MPa were the optimum drilling parameters. In the initial hole, average burr length is 391.75 μm, and delamination of 539.3 μm is noticed. But burr formation is very negligible with delamination of 350.7 μm being observed with uniform circularity (0.979), low taper angle (−0.81354°), and TWR (0.000069 g/min) under optimum drilling conditions through this drilling approach.


2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Ranjit Singh ◽  
Ravi Pratap Singh ◽  
Rajeev Trehan

Purpose This study aims to experimentally investigate the influence of considered process parameters, i.e. pulse on time, pulse off time, peak current and gap voltage, on tool wear rate (TWR) in electrical discharge machining (EDM) of iron (Fe)-based shape memory alloy (SMA) through designed experiments. The parametric optimization for TWR has also been attempted using the desirability approach and genetic algorithm (GA). Design/methodology/approach The response surface methodology (RSM) in the form of Box–Behnken design has been used to scheme out the experiments. The influence of considered process inputs has also been observed through variance analysis. The reliability and fitness of the developed mathematical model have been established with test results. Microstructure analysis of machined samples has also been evaluated and analyzed using a scanning electron microscope (SEM). SEM images revealed the surface characteristics such as micro-cracks, craters and voids on the tool electrode surface. SEM images provide information about the surface integrity and type of wear on the surface of the tool electrode. Findings The input parameters, namely, pulse on time and pulse off time, are major influential factors impacting the TWR. High TWR has been reported at large pulse on time and small pulse off time conditions whereas higher TWR is reported at high peak current input settings. The maximum and minimum TWR values obtained are 0.073 g/min and 0.017 g/min, respectively. The optimization with desirability approach and GA reveals the best parametric values for TWR i.e. 0.01581 g/min and 0.00875 g/min at parametric combination as pulse on time = 60.83 µs, pulse off time = 112.16 µs, peak current = 18.64 A and gap voltage = 59.55 V, and pulse on time = 60 µs, pulse off time = 120 µs, peak current = 12 A and gap voltage = 40 V, correspondingly. Research limitations/implications Proposed work has no limitations. Originality/value SMAs have been well known for their superior and excellent properties, which make them an eligible candidate of paramount importance in real-life industrial applications such as orthopedic implants, actuators, micro tools, stents, coupling, sealing elements, aerospace components, defense instruments, manufacturing elements and bio-medical appliances. However, its effective and productive processing is still a challenge. Tool wear study while processing of SMAs in EDM process is an area which has been less investigated and of major concern for exploring the various properties of the tool and wear in it. Also, the developed mathematical model for TWR through the RSM approach will be helpful in industrial revelation.


2014 ◽  
Vol 660 ◽  
pp. 48-54 ◽  
Author(s):  
Wahaizad Safiei ◽  
Safian Sharif ◽  
Ahmad Fairuz Mansor ◽  
Mohd Halimudin Mohd Isa

This study presents the results of experimental studies carried out to conduct a comprehensive investigation on the influence of Electrical Discharge Machining (EDM) input parameters on characteristics of EDM process. The machining parameters include peak current, servo voltage, pulse ON time and pulse OFF time. The study was conducted using 2 levels of Full Factorial Method in Design of Experiments. The design expert software employed to perform all the data analysis for Full Factorial and Central Composite Design (CCD) experiments. This study evaluates the machining performance of the Stainless Steel 316L using Sodick EDM linear motor series AM3L which employed Copper impregnated graphite diameter 7.0 mm as the tool electrode. The response variables are material removal rate (MRR), electrode wear rate (EWR), surface roughness (SR) and dimensional accuracy. The result shows that the peak current was the most significant factors to all variable responses. The servo voltage does not have significant effects to the machining responses in RSM. Higher current produced higher MRR, EWR, SR and Dimensional Accuracy. Maximum MRR was obtained at peak current range from 27amp to 38amp, pulse on time range from 120μs to 145μs and 60μs of pulse off time. Maximum EWR was obtained at peak current range from 27amp to 37amp, pulse on time range from 140μs to 160μs and 60μs of pulse off time. High probably, the minimum EWR only can be obtained if peak current parameter sets greater than 45amp. Lower dimensional accuracy and SR obtain at 5amp of pulse on time. Higher pulse off time produced lower MRR and EWR.Keywords: EDM Die sinking, Stainless Steel 316L, Copper Impregnated Graphite Electrode, Response Surface Methodology, Surface Roughness, Material Removal Rate, Electrode Wear Rate, Dimensional Accuracy


2014 ◽  
Vol 550 ◽  
pp. 53-61
Author(s):  
R.Arun Bharathi ◽  
P.Ashoka Varthanan ◽  
K. Manoj Mathew

The objective of the present work is to predict the optimal set of process parameters such as peak current (IP), pulse on/off time (TON/TOFF) and spark gap voltage (SV) to achieve minimum Surface roughness (Ra), wire consumption rate (WCR) and maximum material removal rate (MRR). In this work, experiments were carried out by pulse arc discharges generated between ZnO coated brass wire and specimen (IS2062 steel) suspended in deionized water dielectric. The experiments were designed based on the above mentioned four factors, each having three levels. Custom design based Response Surface Methodology (RSM) is used in this research. 21 runs of experiments were constructed based on custom design procedure and results of the experimentation were analyzed analytically as well as graphically. Moreover the surface roughness after machining was measured by Taylor Hobson Surtronic device. Second order regression model has been developed for predicting Ra, WCR and MRR in terms of interactive and higher order machining parameters through RSM, utilizing relevant experimental data as obtained through experimentation. The research outcome identifies significant parametersand their effect on process performance on IS2062 steel. The results revealed that peak current, pulse on-time and their interactions have significant effects on Ra, whereas pulse off time and peak current have significant effects on MRR and it is also observed that peak current and interaction between peak current and pulse off time have significant effects on WCR. The adequacy of the above proposed models has been tested through the analysis of variance (ANOVA).


2021 ◽  
Vol 1018 ◽  
pp. 85-90
Author(s):  
Tran Thi Hong ◽  
Nguyen Anh Tuan ◽  
Bui Thanh Danh ◽  
Le Hong Ky ◽  
Nguyen Hong Linh ◽  
...  

The input parameters in the process of sinking Electrical Discharge Machining (EDM) are the essential enabling factors that need to be determined. In the present work, the influences of the EDM input parameters containing pulse on time (Ton), pulse off time (Toff), discharge current (IP), Server voltage (SV), work-piece diameter (dw) on the surface roughness (SR) in sinking EDM cylindrical shaped part of 9CrSi material were investigated. Taguchi technique and analysis of variance (ANOVA) have been used to identify the weight of EDM factors on SR. The results show that the impact level of Ton, Toff, IP, SP, and dw are 65.55%, 8.66%, 19.17%, 3.14%, and 0.76%, respectively. By analyzing the experimental results, optimum input parameters with the Ton of 6 ms, Toff of 30 ms, IP of 9A, SP of 3V, and dw of 10mm have been determined, that allow getting the best surface roughness.


2010 ◽  
Vol 09 (04) ◽  
pp. 365-370
Author(s):  
VAHID AFSHARI ◽  
CHANGIZ DEHGHANIAN

Square-wave cathodic current modulation was used to electrodeposit fine-grained iron from citric acid bath. The effect of pulse on-time, off-time, peak current density, and total plating time on the grain size, surface morphology, and crystal orientation was determined. X-ray diffraction analysis and modified Williamson–Hall relation were used to determine the average grains size of the coatings. The experimental results showed that an increase in peak current density resulted in considerable refinement in crystal size of the deposits. An increase in the pulse off-time at constant on-time and peak current density resulted in a progressive increase in crystal size. However, the crystal orientation remained unaffected with increasing off-time. The design of the pulse deposition parameters is described in terms of the transport limitations through the diffusion layer and electrochemical interface stability.


2012 ◽  
Vol 472-475 ◽  
pp. 78-81 ◽  
Author(s):  
Mohinder Pal Garg ◽  
Ajai Jain ◽  
Gian Bhushan

This paper investigates the Wire Electric Discharge Machining of Titanium alloy 6-2-4-2.Eight process parameters namely pulse-on time, pulse-off time, peak current, spark gap set voltage, wire feed, wire tension, water pressure, pulse peak voltage and servo feed are varied to study their effect on surface roughness and wire breakage. The experiments are conducted using one-factor-at-a-time approach. Moreover, a few random experiments are also carried to study the phenomenon of wire breakage precisely. The study revealed that surface roughness is directly affected by the pulse-on time, pulse-off time, peak- current, spark gap set voltage and wire tension. Wire feed, Water pressure and pulse peak voltage have negligible effect on the surface roughness. Moreover, wire breakage is predominantly dictated by all the parameters except peak current and pulse peak voltage. An optimum range of input parameters has been bracketed as the final outcome for cutting in terms of surface roughness and to minimize the wire breakage frequency.


Author(s):  
Katerina Mouralova ◽  
Ales Polzer ◽  
Libor Benes ◽  
Josef Bednar ◽  
Radim Zahradnicek ◽  
...  

The unconventional technology of wire electrical discharge machining is a key engineering technology, designed primarily for machining of conventionally difficult machine materials. One of them is nickel alloys, which are majorly used in the aerospace and energy industries. The subject of research in this study was specifically the B1914 nickel-based superalloy, which was subjected to many analyses leading to an overall optimization of its machining using wire electrical discharge machining. In order to determine the effect of machine parameters setup (pulse off time, gap voltage, discharge current, pulse on time and wire feed) on cutting speed, topography, morphology, surface and subsurface layer quality, an extensive Box–Behnken design experiment consisting of 46 rounds was carried out. The analyses of the condition of the surface and subsurface layers were performed, including their chemical composition and changes caused by wire electrical discharge machining. It was found out that the factors like pulse off time, discharge current and pulse on time have the greatest effect on the cutting speed, although from the point of view of surface topography the parameter pulse off time is not significant. The remaining two parameters cause the cutting speed to act against the surface topography i.e. with the increasing cutting speed, the surface topography gets worse and vice versa.


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